Okay, so I had an eye exam yesterday and have a common case of dry eye. The ophthalmologist suggested I take Physician Recommended Nutraceuticals' De (dry eye) fish oil formula. It's a bit pricey and I figured I could find something comparable for less. Along the way I noticed these things and I'm not sure if they've been discussed.
1)
First of all the PRN formula touts that it is the most bioavailable form - "re-esterified triglyceride (rTG)" after purification, where as many other brands, but not all, stop in their processing when the omegas are in ethyl ester form which is less biodegradable. I then thought about Dr. Isaacson's recommended brands. I should first mention he recommends getting as much nutrients as possible from food before supplements (p. 71). He recommends Carlson Super DHA Gems "based on the high amount of DHA per capsule balanced with a reasonable cost". I looked this up and it
appears it is in the ethyl ester form, so less bioavailable. The other he recommends is Life's DHA by Martek. This is an algae form and he recommends it because "some of the most rigorous scientific studies used this exact brand of fish oil in their clinical trials. This also
appears to be in the ethyl ester form, so less bioavailable.
If these most rigorous studies are the same that show E4s don't benefit from fish oil supplements, and if they used the ethyl ester form, one might wonder if the rTG form is preferable for us?
2)
Second, the PRN formula for dry eyes has 560 DHA omega 3 per serving, and 1680 EPA omega 3. It always seems the focus is on DHA and brain health and I got to wondering about the EPA form of omega 3. Are we supposed to avoid high levels of it in our supplements? Are we supposed to include high levels? What does it do?
Here's a very recent, months old, review of the three types of omegas for brain health
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4404917/. It concludes:
"It is vital to consider omega-3 PUFA specific effects when designing and undertaking systematic reviews and meta-analyses, so treatment effects are not lost in the aggregation of results. Overall, a greater understanding of the individual roles of EPA, DPA and DHA in brain health, protection and repair is needed in order to make appropriate dietary recommendations and targeted therapeutic interventions."
I haven't read the paper yet, but I think maybe we are missing huge pieces of the omega 3 puzzle!?
I'm inclined to take a supplement with "sufficient" EPA in it (although no target is known), however I read that EPA is highly oxidized (moreso than DHA) so I'm a little concerned about that, although I think I have a very good redox status. I also eat a ton of wild salmon, nearly every day of the week. I'm assuming it comes with EPA. In spit of all my anti-inflammatory efforts I still have high inflammation and brain fog. I'm now wondering if a lack of sufficient EPA or a poor DHA/EPA ratio (the target for which we have no information) may be at play.
I'm not familiar with Barry Sears work or orientation, but he has this to say at
http://www.zonediet.com/blog/what-are-t ... a-and-dha/:
"Finally, it is often assumed since there are not high levels of EPA in the brain, that it is not important for neurological function. Actually, it is key for reducing neuro-inflammation by competing against AA for access to the same enzymes needed to produce inflammatory eicosanoids. However, once EPA enters into the brain, it is rapidly oxidized (2,3). This is not the case with DHA (4). The only way to control cellular inflammation in the brain is to maintain high levels of EPA in the blood. This is why all the work on depression, ADHD, brain trauma, etc., has demonstrated that EPA is superior to DHA (5)."
Here we might wonder if DHA hasn't worked well for us in part because not enough EPA was included in the studies to offset brain inflammation? (In addition to all the other holes in our roofs!) Martek's Life's DHA which was used in the rigorous studies contains no EPA at all. That would have helped isolate the effects of DHA, but left sooooo many unknowns about how it plays out in terms of the form it's in and relative to quantities of other omega 3, like the recent review describes.